04/05/2025

What is Cellular Senescence?

Cellular senescence is a state in which cells permanently stop dividing in response to stress or damage. The term “senescence” comes from the Latin senescere, meaning “to grow old.”

Understanding the GenAge Dataset

The GenAge Database contains genes potentially associated with human aging and longevity.

Key Statistics

Value
Total.Genes 307
Unique.Symbols 307
Missing.Values 0

Principles of Significance Testing

Statistical hypothesis testing is a framework for making decisions about populations based on sample data.

  • Null Hypothesis (\(H_0\)): A statement of no effect or no difference.
  • Alternative Hypothesis (\(H_1\) or \(H_A\)): A statement that contradicts the null hypothesis.

Mathematical Framework

The test statistic \(t\) for comparing two means is as follows: \[t = \frac{\bar{X}_1 - \bar{X}_2}{\sqrt{\frac{s_1^2}{n_1} + \frac{s_2^2}{n_2}}}\]

Where \(\bar{X}_1, \bar{X}_2\) are sample means, \(s_1^2, s_2^2\) are sample variances, and \(n_1, n_2\) are sample sizes

A note on P-values: \(p\)-value = \(P(T > t)\), where \(T\) is the test statistic under the null hypothesis. A small p-value (typically \(p\) < 0.05) indicates strong evidence against the null hypothesis, leading to its rejection.

Exploration of GenAge

Let’s get an idea of the reasons behind the inclusion of genes in the GenAge database. The dataset contains a column named why, which provides insight into the rationale for each gene’s inclusion.

Visualization of Gene Categories

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